title: [Testosterone impairs insulin sensitivity in 3T3-L1 adipocytes and the related nongenomic mechanisms].
abstract: OBJECTIVE
  To investigate the influence of rapid nongenomic effect of androgen on the insulin sensitivity of mature adipocytes and the molecular mechanism thereof.
  
  
  METHODS
  Fetal mice [corrected] preadipocytes of the line 3T3-L1 were cultured to develop into mature adipocytes. 3T3-L1 adipocytes were pretreated with testosterone of the concentration of 10-9 to approximately 10(-5) mol/L for a short-time 0-30 minutes) or a long-time (24 hours). Insulin (Ins) 200 microl at the concentration 100 micromol/L and 2-deoxy [3H] glucose were added to examine the glucose uptake. Phosphorylation and protein expression of Ins receptor (InsR) and its downstream signaling molecules (Akt and GSK3beta) were analyzed by Western blotting.
  
  
  RESULTS
  The Ins-stimulated glucose uptake after the pretreatment of testosterone for 30 min and 24 h decreased gradually in response to the increasing of the concentration of testosterone with the nadir both at the testosterone concentration of 10(-5) mol/L (both P < 0.05). The phosphorylation levels of InsR, Akt, and GSK3Pbeta were significantly down-regulated by adding of testosterone at the concentration of 10(-6) mol/L for 3-30 minutes (all P < 0.05) or by adding of testosterone at the concentrations of 10(-7) - 10(-6) mol/L for 24 hours (all P < 0.05). The protein expression levels of InsR, Akt, and GSK3Pbeta, however, were not significantly affected by testosterone treatment.
  
  
  CONCLUSIONS
  Rapid nongenomic effect of androgen may contribute to the insulin resistance in adipocytes.
authors.affiliation: Department of Obstetrics, Obstetrics and Gynecology Hospital, Fudan University, Shanghai 200011, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Wen
authors.initials: W
authors.lastname: Xu
authors.forename: Chun-lin
authors.initials: CL
authors.lastname: Su
authors.forename: Jin-fang
authors.initials: JF
authors.lastname: Lin
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000493:pharmacokinetics; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D007328:Insulin / Q000494:pharmacology*; D051379:Mice; D010766:Phosphorylation / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011972:Receptor, Insulin / Q000378:metabolism*; D013739:Testosterone / Q000494:pharmacology*
chemical_list: D007328:Insulin; D013739:Testosterone; D011972:Receptor, Insulin; D000071679:Glycogen Synthase Kinase 3 beta; C000605507:Gsk3b protein, mouse; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3; D005947:Glucose